How to transfer information between pages in ASP.NET using cross-page posting in C#

Software developer can transfer information between pages with technique named cross-page posting. If he wants to do use it he has to define specific, limited methods that extract just the information he need it. Let’s for example he have a page with text boxes as controls for credit card. In this case software developer might decide to add a GetBankCardInfo() method that retrieves the information from text boxes: